Clionadh Spruce is a cool aqua with a metallic finish that is permanent and retails for $5.50. In comparison, Natasha Denona Mint Frost (170SM) is a warm aqua with a metallic finish that is limited edition and retails for $29.00.
Natasha Denona Mint Frost (170SM) is 90% similar — it is lighter, warmer.
